Along with the development of the flat-panel display technology, a Liquid Crystal Display (LCD) has been successfully applied to such a display device as notebook computer, monitor or television. Currently, the LCD has become a mainstream product for information display, and its display quality is continuously improved along with the improvement in the manufacture process.
During the manufacture of an LCD panel, in order to enable liquid crystal molecules to be aligned accurately, it is necessary to coat a polyimide (PI) film onto a surface of an array substrate and a color filter substrate, and then rub the PI film. Hence, a coating process for coating the PI film onto the array substrate and the color filter substrate is very important.
A coating device in the related art mainly includes a frame, a transfer plate, a wheel, a roller and a working table. A glass substrate (e.g., the array substrate or the color filter substrate) is placed onto the working table, and then the transfer plate wrapped onto the roller is in contact with the glass substrate. At this time, due to a transmission function of the working table, the glass substrate is moved on the working table and meanwhile the roller rotates, so as to coat a PI liquid on the transfer plate onto the glass substrate, thereby to form the PI film. Currently, a foreign substance on the transfer plate is removed manually by an operator who enters the coating device. However, through this method, it is impossible to ensure the complete removal of the foreign substance, and thereby the subsequent coating of the PI film may be adversely affected.